"""IMP-47B u4 + u6 — Step 12 AI repair wiring + audit artifact tests.

Scope (this slice):
  * u4 — Helper ``_run_step12_ai_repair`` (src/phase_z2_pipeline.py)
    wires the pipeline's local route-hint helper (``_imp05_route_hint``),
    the frame contract loader (``get_contract``), and a
    templates/phase_z2/families partial reader
    (``_load_frame_partial_html``) into
    ``gather_step12_ai_repair_proposals``.
  * u6 — The gather records flow into ``_write_step_artifact`` under
    ``step12_ai_repair.json``. The audit shape must stay
    JSON-serialisable (no Pydantic / dataclass leakage) so the artifact
    write never raises on real runs.

The router short-circuits when ``settings.ai_fallback_enabled`` is
False (default), so AI=0 for non-AI-route units stays a structural
guarantee. Synthetic naming mirrors tests/test_imp47b_override_provisional.py
(MOCK_ prefix; no real catalog template_id / frame_id leakage).

u5 (PARTIAL_OVERRIDES apply), u7 (coverage invariant), and u8
(slide_status surfacing) are out of scope for this unit.
"""
from __future__ import annotations

import json
from dataclasses import dataclass, field

from src.phase_z2_pipeline import (
    _load_frame_partial_html,
    _run_step12_ai_repair,
    _write_step_artifact,
)


@dataclass
class _StubUnit:
    label: str | None
    provisional: bool
    frame_template_id: str = "MOCK_T_x"
    frame_id: str = "MOCK_F_x"
    source_section_ids: list[str] = field(default_factory=lambda: ["MOCK_S1"])
    raw_content: str = "MOCK_raw"
    v4_rank: int | None = 1
    cardinality: int | None = None
    layout_preset: str = ""
    zone_position: str = ""
    source_shape: str = "paragraph"
    h3_count: int = 0
    char_count: int = 0


# ─── Case 1 : mixed units → per-unit skip_reason classification ─────


def test_mixed_units_classified_by_route_and_provisional_flag():
    """Reject + restructure provisional both route to ai_adaptation;
    use_as_is / light_edit / non-provisional skip without router call.

    With ai_fallback_enabled=False (default) the router returns None,
    so the two ai_adaptation provisional units record
    ``skip_reason='router_short_circuit'``; the rest record their
    structural skip_reason (not_provisional / route_not_ai_adaptation).
    """
    units = [
        _StubUnit(label="use_as_is", provisional=False),
        _StubUnit(label="light_edit", provisional=True),
        _StubUnit(label="restructure", provisional=True),
        _StubUnit(label="reject", provisional=True),
        _StubUnit(label="restructure", provisional=False),
    ]
    records = _run_step12_ai_repair(units)
    assert [r["skip_reason"] for r in records] == [
        "not_provisional",
        "route_not_ai_adaptation:deterministic_minor_adjustment",
        "router_short_circuit",
        "router_short_circuit",
        "not_provisional",
    ]
    assert [r["route_hint"] for r in records] == [
        "direct_render",
        "deterministic_minor_adjustment",
        "ai_adaptation_required",
        "ai_adaptation_required",
        "ai_adaptation_required",
    ]
    assert all(r["ai_called"] is False for r in records)


# ─── Case 2 : reject provisional unit reaches AI gate ───────────────


def test_reject_provisional_unit_reaches_router_short_circuit():
    """Reject + provisional → route_hint=ai_adaptation_required.

    Router short-circuit (flag-off default) is the only thing keeping
    AI from firing; the wiring proves reject is no longer blocked by
    Step 12's bespoke design_reference_only skip (removed by u2).
    """
    records = _run_step12_ai_repair([_StubUnit(label="reject", provisional=True)])
    assert records[0]["route_hint"] == "ai_adaptation_required"
    assert records[0]["skip_reason"] == "router_short_circuit"
    assert records[0]["ai_called"] is False
    # cache_key / fingerprints populated only after the route + provisional
    # gates pass — confirms gather reached the AI-eligible code path.
    assert records[0]["cache_key"] is not None
    assert records[0]["fingerprints"] is not None


# ─── Case 3 : frame visual loader degrades on missing partial ──────


def test_load_frame_partial_html_returns_empty_for_missing_file():
    """__empty__ shell (IMP-30) and any unknown template_id → "".

    Keeps gather() crash-free for the IMP-30 first-render-invariant
    path where the synthesized empty-shell unit has no families partial.
    """
    assert _load_frame_partial_html("__empty__") == ""
    assert _load_frame_partial_html("MOCK_T_does_not_exist") == ""


# ─── Case 4 (u6) : audit artifact write is JSON-serialisable ────────


def test_step12_ai_repair_artifact_writes_json_serialisable_records(tmp_path):
    """IMP-47B u6 — gather records feed ``_write_step_artifact`` as the
    ``step12_ai_repair.json`` audit. Confirms the gather schema contains
    only JSON-native primitives (str / int / None / bool / list / dict)
    so the artifact write never raises on real runs and the audit
    payload preserves per-unit ``route_hint`` / ``skip_reason`` /
    ``ai_called`` for reviewers.
    """
    records = _run_step12_ai_repair([
        _StubUnit(label="reject", provisional=True),
        _StubUnit(label="use_as_is", provisional=False),
    ])
    fpath = _write_step_artifact(
        tmp_path, 12, "ai_repair",
        data={"per_unit": records},
        outputs=["step12_ai_repair.json"],
    )
    assert fpath.is_file()
    assert fpath.name == "step12_ai_repair.json"
    payload = json.loads(fpath.read_text(encoding="utf-8"))
    assert payload["step_num"] == 12
    assert payload["step_name"] == "ai_repair"
    assert payload["step_status"] == "done"
    per_unit = payload["data"]["per_unit"]
    assert len(per_unit) == 2
    assert per_unit[0]["route_hint"] == "ai_adaptation_required"
    assert per_unit[0]["skip_reason"] == "router_short_circuit"
    assert per_unit[0]["ai_called"] is False
    assert per_unit[1]["route_hint"] == "direct_render"
    assert per_unit[1]["skip_reason"] == "not_provisional"